1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * OF graph binding parsing helpers
4  *
5  * Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd.
6  * Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
7  *
8  * Copyright (C) 2012 Renesas Electronics Corp.
9  * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
10  */
11 #ifndef __LINUX_OF_GRAPH_H
12 #define __LINUX_OF_GRAPH_H
13 
14 #include <linux/types.h>
15 #include <linux/errno.h>
16 
17 /**
18  * struct of_endpoint - the OF graph endpoint data structure
19  * @port: identifier (value of reg property) of a port this endpoint belongs to
20  * @id: identifier (value of reg property) of this endpoint
21  * @local_node: pointer to device_node of this endpoint
22  */
23 struct of_endpoint {
24 	unsigned int port;
25 	unsigned int id;
26 	const struct device_node *local_node;
27 };
28 
29 /**
30  * for_each_endpoint_of_node - iterate over every endpoint in a device node
31  * @parent: parent device node containing ports and endpoints
32  * @child: loop variable pointing to the current endpoint node
33  *
34  * When breaking out of the loop, of_node_put(child) has to be called manually.
35  */
36 #define for_each_endpoint_of_node(parent, child) \
37 	for (child = of_graph_get_next_endpoint(parent, NULL); child != NULL; \
38 	     child = of_graph_get_next_endpoint(parent, child))
39 
40 #ifdef CONFIG_OF
41 bool of_graph_is_present(const struct device_node *node);
42 int of_graph_parse_endpoint(const struct device_node *node,
43 				struct of_endpoint *endpoint);
44 int of_graph_get_endpoint_count(const struct device_node *np);
45 struct device_node *of_graph_get_port_by_id(struct device_node *node, u32 id);
46 struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
47 					struct device_node *previous);
48 struct device_node *of_graph_get_endpoint_by_regs(
49 		const struct device_node *parent, int port_reg, int reg);
50 struct device_node *of_graph_get_remote_endpoint(
51 					const struct device_node *node);
52 struct device_node *of_graph_get_port_parent(struct device_node *node);
53 struct device_node *of_graph_get_remote_port_parent(
54 					const struct device_node *node);
55 struct device_node *of_graph_get_remote_port(const struct device_node *node);
56 struct device_node *of_graph_get_remote_node(const struct device_node *node,
57 					     u32 port, u32 endpoint);
58 #else
59 
of_graph_is_present(const struct device_node * node)60 static inline bool of_graph_is_present(const struct device_node *node)
61 {
62 	return false;
63 }
64 
of_graph_parse_endpoint(const struct device_node * node,struct of_endpoint * endpoint)65 static inline int of_graph_parse_endpoint(const struct device_node *node,
66 					struct of_endpoint *endpoint)
67 {
68 	return -ENOSYS;
69 }
70 
of_graph_get_endpoint_count(const struct device_node * np)71 static inline int of_graph_get_endpoint_count(const struct device_node *np)
72 {
73 	return 0;
74 }
75 
of_graph_get_port_by_id(struct device_node * node,u32 id)76 static inline struct device_node *of_graph_get_port_by_id(
77 					struct device_node *node, u32 id)
78 {
79 	return NULL;
80 }
81 
of_graph_get_next_endpoint(const struct device_node * parent,struct device_node * previous)82 static inline struct device_node *of_graph_get_next_endpoint(
83 					const struct device_node *parent,
84 					struct device_node *previous)
85 {
86 	return NULL;
87 }
88 
of_graph_get_endpoint_by_regs(const struct device_node * parent,int port_reg,int reg)89 static inline struct device_node *of_graph_get_endpoint_by_regs(
90 		const struct device_node *parent, int port_reg, int reg)
91 {
92 	return NULL;
93 }
94 
of_graph_get_remote_endpoint(const struct device_node * node)95 static inline struct device_node *of_graph_get_remote_endpoint(
96 					const struct device_node *node)
97 {
98 	return NULL;
99 }
100 
of_graph_get_port_parent(struct device_node * node)101 static inline struct device_node *of_graph_get_port_parent(
102 	struct device_node *node)
103 {
104 	return NULL;
105 }
106 
of_graph_get_remote_port_parent(const struct device_node * node)107 static inline struct device_node *of_graph_get_remote_port_parent(
108 					const struct device_node *node)
109 {
110 	return NULL;
111 }
112 
of_graph_get_remote_port(const struct device_node * node)113 static inline struct device_node *of_graph_get_remote_port(
114 					const struct device_node *node)
115 {
116 	return NULL;
117 }
of_graph_get_remote_node(const struct device_node * node,u32 port,u32 endpoint)118 static inline struct device_node *of_graph_get_remote_node(
119 					const struct device_node *node,
120 					u32 port, u32 endpoint)
121 {
122 	return NULL;
123 }
124 
125 #endif /* CONFIG_OF */
126 
127 #endif /* __LINUX_OF_GRAPH_H */
128